1. Field of the Invention
The present invention relates to the use of antimicrobial peptides, lytic peptides, and peptide-derived antibiotics. More specifically, the present invention relates to enhancement of the antimicrobial activity of these peptides by the use of metal ions. Metal ions exert this enhancing effect when administered or employed prior to, simultaneously with, or after application or administration of these peptides. The present invention provides broad spectrum antimicrobial compositions which are useful in preventative and therapeutic applications, treatment of infections, treatment and disinfection of various types of surfaces, etc.
2. Description of Related Art
Cationic antimicrobial peptides kill bacteria. However, their antibacterial effects are inhibited by various factors, including cations such as Na.sup.++, Ca.sup.++, and Mg.sup.++, present at physiological ionic strength in normal plasma and other body fluids (Zasloff (1987) Proc. Natl. Acad. Sci. USA 84:5449-5453). This limits their usefulness as therapeutic drugs, and has interfered with, or prevented, the development of therapeutically useful cationic antimicrobial peptide compositions.
The discovery of means for overcoming the foregoing problems and augmenting the antibiotic activity of antimicrobial peptides would therefore aid in the development of these peptides as useful drugs, disinfecting agents, etc. In particular, agents that could be easily applied or administered along with these peptides to alter the ionic milieu would facilitate bacterial killing in vitro or in vivo.